This is a research development/planning grant application to initiate collaborative studies with investigators in Shanghai, China to study the incidence of and risk factors for brain atrophy, mild cognitive impairment and dementia (under PAR-05-100, "Brain Disorders in the Developing World: Research Across the Lifespan"). China faces a difficult demographic transition over the next 25 years, with 300 million elderly expected by 2030. The one-child policy initiated in 1979 will! result in the "4-2-1" family structure, with each young person taking care of two parents and four grandparents at home, where care for dementia is traditionally received in Asian countries. Recent studies show that rates for dementia are more similar to Western rates than previously believed and that Alzheimer's disease is the most common type of dementia. We propose to develop a large community-based study in Shanghai to investigate the risk and preventive factors that facilitate or inhibit the expression of dementia for submission in our R01, which will result from this R21 work. A better understanding of these factors could lead to interventions that delay the age of onset of cognitive impairment and dementia, resulting in primary prevention of these disorders in China. The proposed research has a high probability of success in China, where the foreign PI, Dr. Zhen Hong has expertise in population-based studies. China offers many advantages for a study of this type, including significant heterogeneity in the exposures of interest, such as educational attainment and diet. In addition, the Chinese population is known to suffer from a high stroke rate, and vascular risk factors interact importantly with Alzheimer neuropathology to produce dementing syndromes; thus the prevention of vascular disease may have important implications for the prevention of dementia. The specific aims of this planning grant are to: (1) further develop and solidify collaborations with the team in Shanghai and define the scope of the research that will be the focus of an R01 application; (2) assess the Shanghai team's resources and needs in order to successfully conduct community-based research; (3) implement cross-training between the U.S. and Chinese groups in the areas of epidemiology and risk factor assessment, clinical diagnosis, neuropsychological testing and MR imaging for the spectrum of dementia disorders; and (4) conduct pilot studies to generate preliminary data necessary for an R01 application. [unreadable] [unreadable] [unreadable]